1,179 research outputs found
Discourse Markers in the Academic Writing of Arab Students of English: A Corpus-based Approach
This study aims to shed light on the discourse markers used in the academic writing of Arab students of English as a second language within the framework of corpus linguistics. By so doing, an attempt will be made to examine the use of the discourse marker expressing attitude, sequence, cause and result, addition, and comparing and contrasting. For comparison purposes, similar-sized authentic corpus will be used to examine the learners’ use, overuse, and underuse of the target markers. Moreover, the study will provide a detailed account of the possible reasons contributing to the disparity between the two corpora in terms of the use of the target markers. Results show that learners use more discourse markers than native speakers. While this is a general tendency, it still remains feasible to attribute the disparity between the two corpora to learners L1 influence where some of the overused markers spring out naturally and smoothly as they have rhetorical functions in learners’ native tongue
Effects of curcumin on the social behavior, blood composition, reproductive hormones in plasma and brain acetylcholinesterase in cadmium intoxicated mice
AbstractCadmium (Cd) exposure can induce acute lethal health-related threats in humans since it has an exceptional ability to accumulate in living organism tissues and cause toxicological effects. Curcumin (Cur) on the other hand has a wide variety of biological activities and several studies have suggested its potential therapeutic or protective effects against several ailments and infections.To study the effect of Cur on the toxicity of Cd, Swiss–Webster strain male and female mice (sixty each) were divided into 6 groups of ten each at random. Group-1 served as the naïve control and received no treatment. Group-2, 3 and 4 were the experimental controls and were administered once a day with a single oral dose of 50% dimethyl sulfoxide (DMSO), Cur (300mg/kg) or Cd (100mg/kg) respectively, for 2weeks. Group-5 and 6 received Cur and Cd in combination once a day orally for 2weeks except that Cur in a dose of 150 and 300mg/kg to group 5 and 6 respectively, was administered one hour before Cd administration to both groups.After treatment period, the male animals were subjected to social standard opponent test and females were subjected to the tube restraint tests and thereafter, their blood was collected to measure the blood composition indices and level of reproductive hormones. The animals were sacrificed to collect their brain for the estimation of acetylcholinesterase (AChE).Results indicated that Cd significantly increased nonsocial activities in males and latency to first bite in females, whereas the social activities in males and the number of bites in females were significantly decreased. All measured indices of blood composition and levels of progesterone (female) and testosterone (male) in blood and AChE in their brain tissues were significantly decreased due to Cd treatment.However, administration of Cur along with Cd had an ameliorating effect on all the behavioral and biochemical parameters studied herein and reduced the toxicity of Cd significantly and dose-dependently. Thus, Cur may be beneficial for general health and for protection from Cd intoxication
Effect of monosodium glutamate and aspartame on behavioral and biochemical parameters of male albino mice
The present study aimed to investigate the individual and combined effect of mono-sodium glutamate (MSG) and aspartame (ASM) on biochemical, blood parameters and neuro-behavioral aspects of mice. The results indicated that exposure induced many changes in fear and anxiety behavior. The non-social and social behavior of the exposed mice was significantly affected, showing an increase in the former and a decrease in the later stages, respectively. The elements of social behavior including attack, numbers of fights and bites, naso-nasal and naso-genital contacts were decreased significantly. The latencies to threat and attack and first bite were increased significantly. Locomotor activity and neuromuscular coordination (grip strength) were decreased in treated animals as compared to the control group. There was a significant decrease in the red blood cell count, packed cell volume, hemoglobin concentration, white blood cell count platelets count and testosterone hormone in the treated males. The activity of acetylcholinesterase enzyme decreased as compared to the control. In conclusion, the current study indicated that exposure to food additives MSA and ASM was dangerous to mice in relation to behavior and biochemical analysis. In addition, these food additives need more scientific researches to investigate their effect on other parameters.Key words: Mono-sodium glutamate, mono-sodium aspartame, fear and anxiety, locomotory behavior, grip strength, acetylcholinesterase
CURCUMIN ATTENUATES LEAD (Pb)–INDUCED NEUROBEHAVIORL AND NEUROBIOCHEMICAL DYSFUNCTION: A REVIEW
Lead is one of the common chemical elements that is assigned the symbol Pb which came from the Latin Plumbum. Pb is widely used in the field of coating, refine and glaze ceramics and pottery. It is still used in the production of products like water pipes, cooking utensils and cooking utensils. In addition it is also used in insulation of building ceilings, cable coverage and military industries. Lead enter the environment from those uses and from the environment it enter into the living organisms. Lead accumulates in many humanorgans, but the brain is the target organ of lead accumulation. Neurotoxicity of lead is, one of lead toxicity, caused many symptoms. There are many behavioral and biochemical modifications induced by lead toxicity like learning and memory deficits, anxiety disorders, social and sexual behavior modifications and neurotransmitter system deficits. Curcumin is a bioactive natural phytochemical phenolic compound (diferuloylmethane) extracted from the rhizome of Curcuma longa. Most studies indicated the role of curcumin in reducing the damage of lead toxicity. In the current review, emphasis was based on the toxicity of lead and its effect on behavior and some neurotransmitters related to behavior. The effect of curcumin is improving the neurotoxicity and behavioral toxicity of lead
Almost unbiased ridge estimator in the zero-inated Poisson regression model
The zero-inflated Poisson regression (ZIP) model is a very popular model for count data that have extra zeros. In some situations, the count data are correlated and so multicollinearity exists among the explanatory variables. Thus, the traditional maximum likelihood estimator (MLE) becomes not a reliable estimator because the mean squared error (MSE) becomes inflated. The ridge estimator (RE) is used to overcome this problem. In this work, an almost unbiased ridge estimator for the ZIP model (AUZIPRE) is proposed to tackle the multicollinearity problem in count data. We investigate the behavior of the proposed estimator using a simulation study. Using the MSE measure, the results of the proposed estimator are compared with those of the RE and the MLE. Furthermore, we apply the proposed estimator on a real dataset. The results show that the performance of AUZIPRE outperforms for that of the RE and the MLE in the existing of the multicollinearity among the count data in the ZIP model.Publisher's Versio
Local wheat peel as a solid surface to remove Azure B dye from aqueous solution:Equilibrium isotherms and thermodynamic study
In this research local wheat peel was used as an adsorbent surface for removal of Azure B (AB) dye from the aqueous solution. The adsorption process was performed at different experimental parameters, equilibrium time, temperature, ionic strength and solution pH. The isotherms of adsorption are of H-type as compared with Giles curves and the adsorption data were coincide with Freundlich equation. The adsorption kinetic data were analyzed using pseudo- first and second order kinetic models. The effect of temperature was studied and the amount of dye adsorbed was found to increase with the increasing of temperature from 25 to 50 oC. The values of thermodynamic functions like enthalpy and entropy have been estimated. The quantity of adsorbed dye on the wheat peel increase according to the sequence follows: pH 9.3? 8 ? 7 ?6 ?5.2.The adsorption phenomenon is influenced by the sodium chloride concentration of solution. The obtained data refer to a decrease in amount of Azure B adsorbed in the existence of electrolyte
Some almost unbiased ridge regression estimators for the zero-inflated negative binomial regression model
Zero-inflated negative binomial regression (ZINB) models are commonly used for count data that show overdispersion and extra zeros. The correlation among variables of the count data leads to the presence of a multicollinearity problem. In this case, the maximum likelihood estimator (MLE) will not be an efficient estimator as the value of the mean squared error (MSE) will be large. Several alternative estimators, such as ridge estimators, have been proposed to solve the multicollinearity problem. In this paper, we propose an estimator called an almost unbiased ridge estimator for the ZINB model (AUZINBRE) to solve the multicollinearity problem in the correlated count data. The performance of the AUZINBRE is investigated using a Monte Carlo simulation study. The MSE is used as a measure to compare the results of the proposed estimators with those of the ridge estimators and the MLE. In addition, the AUZINBRE is applied to a real dataset
- …